Chain wrench



H. E. PFAFF CHAIN WRENCH March 26, 1929.

Filed Dec. 23, 1927 2 SheetsShe'"t H'a rrl E. Phan- .b lilbnii fm his a ffarmrq I March 26, 1929.

H. E. PFAFF 1,706,411

CHAIN WRENCH Filed Dec. 23, 1927 2 Sheets-Sheet 2 FIG INVENTOR:

Harry I. Phi}?- q his afforney l atente tl Mar. 26, 1929.

n STATES PATENT, OFFICE.

HARRY E. PFAFF, 0F WARREN, OHIO,

ASSIGNOR TO CANADA.

ALEX METHERELL, OF HAMILTON,

CHAIN WRENCH.

Application filedDecember 23, 1927. Serial No. 242,162.

8 a chain wrench having this characteristic,

which is adapted to grip articles of various sizes, and to engage an article of small diameter as firmly as an article of'relatively great diameter.

A further object of the invention is to provide a chain wrenchin which the locking action of the wrench during its useis wholly automatic, and which avoids the use of springs or operating levers in order to secure arlocked engagement of the gripping chain of the wrench when leverage is brought to bear upon an article to be gripped.

In the accompanying drawings Figure 1 is a side elevation of the chain wrench of the present invention, showing the chain thrown around a section of pipe, and the handle in the position to receive the chain; Figure 11 is a side elevation, showing the position of the parts after the chain is positioned and locked by moving the handle'downward; Figure 111 is aside elevation of the wrench illustrating its position inverted for counter rotation; Figure 1V is a fragmentary side elevation illustrating the engagement of the chain of the wrench with an article of relatively small diameter, and Figure V is a plan view of the relative positionthe wrench, illustrating ingof the parts, and showing the engagementof thewrench with a flange of relatively slight :Wldth. 5

In the drawings the reference numeral 1 designates the handle member of the wrench, whichis bifurcated adjacent its forward extremity-to provide a y'oke 2 embracing the gripping jaw 3 of the wrench, and providing a mounting space for the chain locking means thereof. f' p p r The gripping jaw 3 of the wrench is pivotally mounted in the yoke 2 by means of a pivot pin 4 passing through the yoke and jaw, and ward gripping engage the face. 5 formed on an arc to as a p pe. The chain6 of the wrench, which on a pin 15, which is mounted in the to one side of the longitudinal center lineperiphery of the pipe.

ving engagement with has a roughened, or serrated, for- .1 serves surface of-a circular object, such I is of the usual type comprising center links 7 and side links 8, is attached in the seat 90f the jaw 3 by means of a pin '10.

Therearward face 11 within the yoke 2 is irregularly curved to provide a curved ex tension 12 and an indentation 13 for engagingthe chain 6 to lock the same in gripping position. A dog l lis eccentrically pivoted yoke '2' thereof. The face 16 of the dog which cooperates with the chain 6 is curved to provide extensions 17 and 18, which cooperate with;

the face 11 to engage the chain in locked position.

With particular reference to Figure I of the drawings the chain 6 has been passed around a pipe A, and the contacting face 5 of the aw 3 brought'into contact with the "The free end of the chain 6 is then drawnthrougli the space in the yoke which lies to the rear of dog l i. During this action the dog 14 oscillates freelyand permits the insertion of the chain.

Figure 11 of the drawings illustrates the locking of the chain 6. In this position it will be noted that the handle 1 of the wrench has been lowered from its positionas shown in Figure L'while the position of the jaw 8 of the wrench remains substantially unchanged. This action produces a tendency for the edge 17 of the dog l lto swing outwardly, causing the edge 18 to bear rearwardly on the chain, and to force it into lockthe protuberance 12 and indentation 13Iof the face 11. 'During this action the chain Gisforcedthrou'gh the yoke 2 of the wrench a greater distancethan it may be drawn by hand.

It will be further noted that the line from the center of the pivot pin 15of the dog, as shown in dotted line a is longer than the line between the center of the pivot pin and the pin of the edge or extension 18, as shown by the dotted line b. This gives a greater effective lever arm for rotating the edge 18 inwardly, than for the reverse of this action. After the chainis locked, in the position of the parts shown in Figure II of the'drawings, further rotation of the handle member to still further tighten this locking engagement, which isnot broken until the handle is rotated in a counter direction. Figure III shows the wrench locked around the pipe A for rotation counter to thatshown in inwardly from the ends in the position shown in Fig. I while the,

chain is being passed through yoke 2.

Figure IV ofthe drawings illustrates the gripping of a circular object B of relatively small'diameter. This object is engaged, similarly to the object A of relatively great diameter, between the gripping face 5 of the jaw 3 and the chain 6. In order that the chain 6 may be brought sufficiently close to the jaw is slotted the face 5 0f the jaw,

of the face 5, as at 20, so that the chain may lie in these slots to closelyengage the object B. After the chain has been locked in the body of the Wrench, the slight swivelling movement of the jaw produced by further rotation of the handle produces a tendency toward a tighter gripping of the object B.

What I claim is:

1. A chain wrench comprising a handle member having a chain receiving passage with a chain engaging seat, a pivotal]v 1 mounted jaw on said handle member, a grip ping chain attached to said jaw, and an eccentrically pivoted locking member having a contacting face with two chain engaging points thereon arranged to coact with the chain engaging seat of the handle memher.

2. A chain wrench comprising a handle,

member having a chain receiving passage Wltl'l a chain engaging seat, a pivotally mounted jaw on said handle member, a grip ping chain attached to said jaw, and a locking member e'ccentrically pivoted in the chain receiving passage of the handle member and having two chain engaging points so arranged with respect to the to the pivotal cen ter of the locking member and the chain engaging seat of the handle member that they automatically lock the chain upon movement of the handle member when the chain em- I braces an object to be gripped.

3. A chain wrench comprising a handle member having a chain receiving passage with a chain engaging seat, a protuberance on said seat, a pivotally mounted jaw on said handle member, a gripping chain attached to said jaw, a locking member pivotally mounted in the chain receiving passage, a protubermice on said locking member arranged to coact with the protuberance on the seat of the handle member to grip the chain, and a "member having a, chain point on the locking member arranged to engage the chain to cause movement of the member for producing such gripping action upon movement of the handle member when the chain embraces an object to be gripped.

4:. A chain wrench comprising a handle member having a chain receiving passage with a chain engaging seat, a protuberance on said seat, a pivotally mounted jaw on said handle member, a gripping chain attached to said jaw, a locking member pivotally .mounted in the chain receiving passage, a

protuberance on said locking 'member arranged to coact with the protuberance on the seat of the handle member to grip the chain, and a point on the locking member arranged to engage the chain to cause movement of the" member for producing such gripping action upon movement of the handle member whenthe chain embraces an object to be gripped,

the distance from the pivotal center of the a locking member to the gripping protuberance being less than the distance from the pivotal center of the locking member to the actuating point thereon. Y j I 5. A chain wrench comprising a handle member having a chain receiving passage with a chain engaging seat, a' pivotally mounted jaw onsaid handle member, a gripping chain attached to said jaw, said jaw having slots extending inwardly from thecor ners of the gripping face thereof to provide seats for the chain, and an eccentrically pivoted locking member having a contacting face with two chain engaging points thereon arranged to coact with the chain engaging seat of the handle member. l

6. A chain wrench comprising a handle member having a chain receiving passage with a chain engaging seat, a' pivotally mounted jaw on said handle member, a gripping chain attached to said jaw, said jaw having'slots extending inwardly from the corners of the gripping face thereof to provide seats for the chain, and a locking member eccentrically pivoted in the chain receiving pas sage of the handle member and having two chain engaging points so arranged with respect to the pivotal center ofthe member and the chain engaging seat of the handle member that they automatically lock the chain upon movement of the handle member when the chain embraces an object to be gripped.

7. A chain wrench comprising a handle receiving passage with a chain engaging seat, a protuberance on said seat, a pivotally mounted jaw on said handle member, a gripping chain attached to said jaw, said jaw having slots extending inwardly from the corners of the gripping face thereof to provide seats for-the'chain, a lookmember arranged to coact with the protuberance on the seat of the handle memher to grip the chain, and a point on the locking member arranged to engage the chain to cause movement of the member for producing such gripping action upon movement of the handle member when the chain embraces an object to be gripped. v I

8. A chain wrench comprising a handle member having a chain receiving passage with a chain engaging seat, a protuberance on said seat, a pivotally mounted jaw on said handle member, a gripping chain attached to said jaw, said jaw having slots extending inwardly from the corners of the gripping face thereof to provide seats for the chain, a locking member pivotally mounted in the chain receiving passage, a protuberance on said locking member arranged to coact with the protuberance on the seat of the handle memher to grip the chain, and a point on the lock ing member arranged to engage the chain to cause movement of the member for producing such gripping action upon movement'of the handle member when the chain embraces an object to be gripped, the distance from the pivotal center of the locking member to the gripping protuberance being less than the distance from the pivotal center of the locking member to the actuating point thereon.

11gl witness whereof, I hereunto set my" han v HARRY E. PFAFF, 

